This invention relates to a method of sewing a buttonhole, more particularly, to an improved method in which the final stitching is made in the forward direction and in which buttonholes which are perpendicular to the edge of a garment may be initiated on the end of the buttonhole nearest the edge of the garment.
The buttonhole produced on presently known electronically controlled sewing machines utilizes a travelling buttonhole foot in which a button determines the location of stops which actuate, through a paddle arrangement, switches in the sewing machine to initiate the next series of stitches for the buttonhole. In these prior art sewing machines the buttonhole sequence includes (1) making a first bar (2) implementing narrow bight cording stitches on the left side in the forward feed direction, (3) completing the second bar, (4) finishing the left side with wide bight covering stitches in the reverse direction, (5) implementing the narrow bight cording stitches on the right side in the forward direction, and (6) making wide bight covering stitches in the reverse feed direction over the right side cording stitches. This system was developed and is successful in eliminating the need for adjusting balance, i.e., having the stitches on one side of the buttonhole have the same appearance as the stitches on the other side thereof. However, since the final stitches are accomplished in the reverse direction, they do not have the same appearance as stitching in the forward direction. Since most of the stitching of sewing machines is accomplished in the forward direction, considerable care and attention is devoted to insure that the forward stitch presents a good appearance. For example, in some machines there is a greater tendency to "halo" in the reverse direction, that is to have an extra amount of top thread between stitches, which condition is not evident in the forward direction.
Simply reversing the sequence for making the buttonhole so that the cording stitches are accomplished in the reverse direction and the final covering stitches in the forward direction is not a solution in as much as a problem could occur in the making of a buttonhole which is perpendicular to the edge of a garment. In such a buttonhole, it is desirable that the initial bar tack begin adjacent the edge of the garment since any variation which may take place in the length of a buttonhole will not be as noticeable on the side away from the edge of the garment as it would be next to the edge. Thus, to position the work material adjacent an operator as is usual, and to reverse the above sequence would initiate the buttonhole on its inner side and not adjacent the edge.
What is required is a method for making a buttonhole having the seemingly adverse requirements for accomplishing the final stitches in the forward direction and at the same time having the initial bar tack in a forward direction with respect to the final bar tack.